CN115547244A - Decoupling circuit, driving IC and display device - Google Patents
Decoupling circuit, driving IC and display device Download PDFInfo
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- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
- G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
- G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
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- G—PHYSICS
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- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2300/00—Aspects of the constitution of display devices
- G09G2300/04—Structural and physical details of display devices
- G09G2300/0404—Matrix technologies
- G09G2300/0408—Integration of the drivers onto the display substrate
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- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2310/00—Command of the display device
- G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
- G09G2310/0243—Details of the generation of driving signals
- G09G2310/0248—Precharge or discharge of column electrodes before or after applying exact column voltages
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2310/00—Command of the display device
- G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
- G09G2310/0264—Details of driving circuits
- G09G2310/0272—Details of drivers for data electrodes, the drivers communicating data to the pixels by means of a current
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2310/00—Command of the display device
- G09G2310/02—Addressing, scanning or driving the display screen or processing steps related thereto
- G09G2310/0264—Details of driving circuits
- G09G2310/0291—Details of output amplifiers or buffers arranged for use in a driving circuit
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2320/00—Control of display operating conditions
- G09G2320/02—Improving the quality of display appearance
- G09G2320/0257—Reduction of after-image effects
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- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2320/00—Control of display operating conditions
- G09G2320/06—Adjustment of display parameters
- G09G2320/0626—Adjustment of display parameters for control of overall brightness
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- G—PHYSICS
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- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G2320/00—Control of display operating conditions
- G09G2320/06—Adjustment of display parameters
- G09G2320/0626—Adjustment of display parameters for control of overall brightness
- G09G2320/064—Adjustment of display parameters for control of overall brightness by time modulation of the brightness of the illumination source
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Abstract
The application relates to a decoupling circuit, a driving IC and a display device, which comprise a pre-charge module and a constant current driving module, wherein the output end of the pre-charge module and the output end of the constant current driving module are connected together to be used as a channel output end; in one display unit, when PWM is larger than 0, the working states of the pre-charging module are pre-charging V1, pre-charging closing and pre-charging V2 in sequence, the constant current driving module is started to light the lamp beads in an area corresponding to the pre-charging closing based on the PWM, and the voltage of the channel output end is V3 at the moment; when the PWM is equal to 0, the constant current driving module is closed, and the output states of the pre-charging module are pre-charging V4, pre-charging V5 and pre-charging V6 in sequence; wherein, (V1-V3) - (V4-V5) = K1, (V2-V3) - (V6-V5) = K2, and K1 and K2 are constants, so that the decoupling effect of the display screen can be improved.
Description
Technical Field
The application relates to the field of integrated circuits, in particular to a decoupling circuit, a driving IC and a display device.
Background
The LED display screen is generally composed of m rows by n columns of lamp beads, the row driving IC and the column driving IC are used for display driving respectively, due to parasitic capacitance on a row line and a column line, a coupling phenomenon is generated in the LED display process, and in addition, the parasitic capacitance can also enable the LED display screen to generate phenomena such as upper ghost, lower ghost and the like. The coupling phenomenon of the LED display screen is mainly influenced by various parasitic parameters, board end wiring, lamp bead parameters and the like on the PCB, and the coupling phenomenon can only be reduced but not completely eliminated. The generation principle is as shown in fig. 1, D11 and D12 are two lamp beads in the same row connected by common anode, and two adjacent LEDs are located on the PCB, there is a small parasitic capacitance Cm between the cathodes of D11 and D12, sr1a is turned on when scanning the first row, if it is assumed that D11 is off at this time and the gray scale is 0, sc1a is turned on, if it is assumed that D12 is on at this time and the gray scale is large, sc2a is turned on, since the cathode of D11 is in an uncontrolled floating state at this time, it is neither turned on nor in a ghost elimination state, D12 is switched from a ghost elimination state to a lower voltage at which the cathode voltage jumps from a higher voltage to a conducting state at the moment when D12 is switched from the ghost elimination state to the conducting state, as shown in the waveform on the right side of fig. 1, due to the existence of the capacitance Cm, the signal will be coupled to the cathode of D11, resulting in a negative jump of the cathode voltage of D11, D11 is slightly turned on, as shown in waveform on the left side. This is also commonly referred to as high-low gray coupling because the high gray LEDs are coupled to the low gray or 0 gray neighboring LEDs. In addition to the high-low gray coupling imagination, the phenomenon of cross-plate coupling refers to vertical lines with obvious brightness boundaries at the boundaries of a spliced screen, and the phenomenon is called the phenomenon of cross-plate coupling. The essence of the cross-board coupling is that the rear-level gray scale continuously has a coupling effect on the front-level gray scale, the clamping voltage of the front-level gray scale is continuously raised, the coupling effect is the lighter the rear-level gray scale coupling is, the more the front-level gray scale coupling is, the lower the brightness part is, and therefore, a remarkable brightness boundary line can be seen at the positions where the row pipes are disconnected and the modules are physically spliced.
In order to reduce the influence of parasitic capacitance, the traditional mode is to clamp the lamp bead to the same voltage before the lamp bead is displayed through a pre-charging circuit before the display, and the voltage jump generated in the process releases the charge of the parasitic capacitance.
Disclosure of Invention
The utility model aims to overcome prior art's not enough, provide a decoupling circuit, drive IC, display device, can not only eliminate the last ghost of LED display screen, lower ghost phenomenon, the coupling phenomenon of reduction display screen that can also be very big.
The purpose of the application is realized by the following technical scheme:
the first aspect of the present application provides a decoupling circuit, including a pre-charge module and a constant current driving module, where an output terminal of the pre-charge module and an output terminal of the constant current driving module are connected together to serve as a channel output terminal;
in a display unit, when PWM is larger than 0, the working state of the pre-charging module is pre-charging V1, pre-charging closing and pre-charging V2 in sequence, the constant current driving module turns on a lamp bead in an area corresponding to the pre-charging closing based on PWM, and the voltage of the output end of a channel is V3 at the moment;
in one display unit, when the PWM is equal to 0, the constant current driving module is closed, and the output states of the pre-charging module are pre-charging V4, pre-charging V5 and pre-charging V6 in sequence;
wherein, (V1-V3) - (V4-V5) = K1, (V2-V3) - (V6-V5) = K2, and K1 and K2 are constants.
In this application, through the electric potential of adjusting precharge V1, V2, V4, V5, V6 for under the condition that PWM that decoupling circuit shows the lamp pearl is greater than 0 and PWM equals 0, decoupling ability is the same, can realize best decoupling effect, ghost phenomenon under also can eliminating through precharge V1, V2, V4, V6 simultaneously.
Further, when the PWM is greater than 0, the duration of the precharge off state is greater than or equal to the display time of the PWM.
Furthermore, precharge V1, precharge V2, precharge V4, precharge V5, precharge V6 all can not be enough to make the lamp pearl light.
Preferably, (V1-V3) is equal to or about equal to (V4-V5) and (V2-V3) is equal to or about equal to (V6-V5).
Further, in the common anode display panel, V3< V5, and in the common cathode display panel, V3> V5.
Further, in the common cathode display screen, V3> V1, V3> V2, V5> V4;
in the common anode display screen, V3 is less than V1, V3 is less than V2, and V5 is less than V4.
Optionally, the precharge module includes a closed state between V1 and V3, between V3 and V2, between V4 and V5, and between V5 and V6, and the duration of the closed state is t, where t ≧ 0.
Further, the display unit refers to a minimum display grouping of the gradation data within one sub-frame.
The second aspect of the present application provides another decoupling circuit, including a pre-charge module and a constant current driving module, where an output terminal of the pre-charge module and an output terminal of the constant current driving module are connected together to serve as a channel output terminal;
in a display unit, when PWM is larger than 0, the working state of the pre-charging module is pre-charging V1 and pre-charging off in sequence, the constant current driving module turns on a lamp bead in an area corresponding to the pre-charging off based on PWM, and the voltage of the output end of a channel is V3 at the moment;
in one display unit, when the PWM is equal to 0, the constant current driving module is closed, and the output states of the pre-charging module are pre-charging V4, pre-charging V5 and pre-charging closing in sequence;
wherein, (V1-V3) - (V4-V5) = K1, and K1 is a constant.
A third aspect of the present application provides a driver IC comprising a decoupling circuit as described in the first or second aspect.
A fourth aspect of the present application provides a display device comprising a driver IC and a display panel, the driver IC being as described in the third aspect, the display panel comprising an LED display screen.
The beneficial effect of this application is: compared with the traditional decoupling, the lamp bead display device has the advantages that different pre-charging potentials are given by clamping the same voltage before the lamp bead display according to the pre-charging in the prior art and eliminating the difference of parasitic capacitance according to the requirement of different lamp beads, so that when PWM =0 and PWM > 0, the decoupling capacity is the same, the charging potentials required by different lamp beads are different, and the decoupling effect of the display screen is improved on the whole.
Drawings
FIG. 1 is a schematic diagram of a coupling phenomenon caused by parasitic capacitance;
FIG. 2 is a circuit diagram of an embodiment of the present application;
FIG. 3 is a schematic view of one embodiment of the present application where PWM is greater than 0;
FIG. 4 is a schematic view of another embodiment of the present application at PWM greater than 0;
FIG. 5 is a schematic diagram of one embodiment of the present application where PWM is equal to 0;
FIG. 6 is a schematic diagram of another embodiment of the present application at PWM equal to 0;
FIG. 7 is a schematic view of another embodiment of the present application at PWM greater than 0;
FIG. 8 is a schematic view of another embodiment of the present application where PWM is equal to 0;
fig. 9 is a schematic diagram of the principle of gray scale data display.
Detailed Description
The technical solution of the present application is further described in detail with reference to the following specific examples, but the scope of the present application is not limited to the following.
A first aspect of this embodiment provides a decoupling circuit, which includes a pre-charge module and a constant current driving module, where an output terminal of the pre-charge module and an output terminal of the constant current driving module are connected together to serve as a channel output terminal.
Referring to fig. 2, the output terminal of the pre-charging module and the output terminal of the constant current driving module are connected in common, wherein a switch is arranged between the constant current driving module and the channel output terminal OUT, the switch is controlled by display data, the display data is a PWM signal of the current display unit, when the PWM is greater than 0, the switch is closed, the constant current driving module outputs a constant current, and the lamp bead is turned on. PWM is a waveform signal representing gray scale data, and if PWM is greater than 0, the represented gray scale data is displayed to be greater than 0. When the PWM is equal to 0, the switch is always off, namely, the constant current driving module is in an off state with the output end, which is equivalent to the turning off of the constant current driving module. The precharge module performs a voltage precharge output based on a reference voltage and a precharge control signal for controlling an output state (on or off) of the precharge module and a voltage value of the output.
The pre-charging module and the constant current driving module cannot be started at the same time, when PWM display is carried out, the pre-charging module is closed, the constant current driving module is started to output a constant current to light the lamp beads, the pre-charging module is started to output pre-charging before and after the PWM display is finished, and the constant current driving module is closed. In other words, the pre-charge module and the constant current driving module belong to an output mode, but the pre-charge module and the constant current driving module can be turned off at the same time.
It should be noted that, in the common anode LED display screen and the common cathode LED display screen, the connection of the pre-charge module and the constant current drive module are different, and as shown in fig. 2 (a), the common anode LED display screen is provided, the constant current drive module is grounded, and the pre-charge module is connected to the power supply, and in the common cathode LED display screen shown in fig. 2 (b), the constant current drive module is connected to the power supply, and the pre-charge module is grounded.
The pre-charge module outputs based on a pre-charge control signal, wherein the pre-charge control signal can be configured by a register or adjusted manually, the reference potential is a reference voltage provided to the pre-charge module, and the gain adjustment is performed based on the reference voltage, so that different pre-charge potentials are output.
In one display unit, when the PWM is greater than 0, the working state of the precharge module is precharge V1, precharge off, precharge V2 in sequence. The constant current driving module enables the lamp beads to be lightened based on PWM opening in an area corresponding to pre-charging closing, the voltage of the output end of the channel is V3 at the moment, and the duration time of the pre-charging closing state is more than or equal to the display time of the PWM so as to ensure normal display of the PWM. That is, the display of the PWM is completed within a time period corresponding to the precharge off state, and the display time of the PWM is equal to or less than the duration of the precharge off state. On the time axis, the output voltages of the channel output ends are V1, V3, and V2 in sequence, and the principle can be referred to fig. 3.
Fig. 3 is a timing diagram of the PWM display state, the precharge module operation state, and the constant current driving module operation state in one display unit. The constant current driving module is only started in a time period for displaying PWM to enable the lamp beads to be lightened, the constant current driving modules in other time periods are all closed, and the lamp beads are extinguished. That is, the time period for displaying the PWM and the time period for turning on the constant current driving module completely coincide with each other, as shown in fig. 3.
The period of displaying the PWM is completely within the precharge off period, and for example, the period of displaying the PWM may be aligned with the start of the precharge off period, aligned with the end of the precharge off period, aligned with both the start and the end of the precharge off period (i.e., the period of displaying the PWM coincides with the precharge off period), or misaligned with both the start and the end of the precharge off period (i.e., the period of displaying the PWM is within the precharge off period) as shown in fig. 3.
As shown in fig. 3, the duration of the precharge off state is longer than the display time of the PWM, the start point of the precharge off state leads the start point of the display PWM by a time td1, and the end point of the precharge off state is delayed by a time td2 from the end point of the display PWM, wherein td1 and td2 are both equal to or longer than 0 display cycles, that is, the duration of the charge off state is equal to or longer than the display time of the PWM.
As shown in fig. 4, the precharge off state lasts for a time equal to the display time of the PWM, that is, the charge off state and the display time of the PWM coincide and are equal, and td1 and td2 are both equal to 0.
In one display unit, when the PWM is equal to 0, the constant current driving module is closed, and the output states of the pre-charging module are pre-charging V4, pre-charging V5 and pre-charging V6 in sequence. Because PWM equals 0, no data display of degree promptly, the lamp pearl is in the state of extinguishing out in this display element, and constant current drive module closes in the display element whole journey, and precharge module satisfies in proper order in the display element and exports precharge V4, precharge V5, precharge V6 three states can.
Referring to fig. 5, in a display unit, since PWM is equal to 0, the PWM display state is empty, that is, the PWM is at low level, it can also be understood that the PWM is in the off state in the display unit, and its corresponding constant current driving module is also in the off state all the time. The output states of the precharge module are precharge V4, precharge V5, and precharge V6 in sequence, wherein the durations of precharge V4, precharge V5, and precharge V6 have no fixed requirement and only need to be greater than 0, and referring to the embodiment shown in fig. 5, the precharge V4, precharge V5, and precharge V6 are seamlessly connected to occupy the whole display unit. The pre-charging V5 is used for simulating the voltage for turning on the lamp beads, but is not enough for turning on the lamp beads.
Referring to fig. 6, the modification is made to the duration adjustment of the pre-charges V4, V5 and V6, that is, a closed state is inserted between the pre-charges V4, V5 and V6, and the pre-charges V4, V5 and V6 are intermittently, rather than continuously, wherein the closed state is td3 and td4. Similarly, precharge V4 and precharge V5 may be continuous, and precharge V5 and precharge V6 may be discontinuous, or precharge V4 and precharge V5 may be discontinuous, and precharge V5 and precharge V6 may be continuous. It is only required to satisfy that three states of precharge V4, precharge V5 and precharge V6 appear in sequence in one display unit, namely that the values of td3 and td4 are both greater than equal 0.
Further, in order to improve the decoupling effect, the pre-charges V1, V2, V4, V5 and V6 in the present embodiment should satisfy a constant relationship.
That is, (V1-V3) - (V4-V5) = K1, (V2-V3) - (V6-V5) = K2, and K1 and K2 are constants. The constants K1 and K2 are not fixed values, and the values of K1 and K2 are slightly changed based on different LED display arrays. Ideally, (V1-V3) = (V4-V5), (V2-V3) = (V6-V5), that is, the constant K1= K2=0, and in practical applications, a test may be performed according to a specific LED display screen to determine the value of the constant, and generally, the values of K1 and K2 fluctuate around 0, that is, (V1-V3) is equal to or approximately equal to (V4-V5), (V2-V3) is equal to or approximately equal to (V6-V5). In order to simplify the test process, 0 can be directly taken, and the decoupling effect is also obviously improved compared with the prior art.
It should be noted that the pre-charge module is used to eliminate the influence of the parasitic capacitance and does not turn on the lamp bead, so that the pre-charges V1, V2, V4, V5, and V6 are not enough to turn on the lamp bead.
The effect of precharging is to reduce the influence of parasitic capacitance on display coupling, so that the lamp beads are lighted when the precharged voltage is not enough. But provide a voltage jump process, utilize this jump voltage to release the electric charge that produces because of the parasitic capacitance, based on formula Q = CV, Q represents the electric charge amount, C represents the electric capacity, V represents the voltage, for a certain lamp pearl, its parasitic capacitance C is fixed, therefore the electric charge size that will eliminate the parasitic capacitance and release depends on the value of voltage, and will make the parasitic capacitance release the electric charge and need a voltage jump, therefore precharge V1, precharge V2, precharge V4, precharge V5, precharge V6 make this voltage jump, are used for releasing the parasitic capacitance and produce the electric charge, after the neighbouring lamp pearl of this lamp pearl is lighted, this lamp pearl will not be turned on a little because of the parasitic capacitance, thus reduce the coupling phenomenon.
Based on the driving characteristics of the common anode display panel and the common cathode display panel, in the common anode display panel, V3< V5, and in the common cathode display panel, V3> V5. Further, in the common cathode display screen, V3> V1, V3> V2, V5> V4; in the common anode display screen, V3 is less than V1, V3 is less than V2, and V5 is less than V4.
Generally, in an anode display screen, the voltages may be configured to:
V1≈3.5V，V3≈1V，V2≈3.5V，V4≈5V，V5≈3V，V6≈3.5V。
further, the display unit in this application refers to a minimum display group of the gray data in one sub-frame, and may be understood as a minimum group of the PWM display. Referring to fig. 9, which is a schematic diagram of the display of the line scan driver chip, it is known based on the common sense that the display screen is composed of a plurality of continuous frames, the driver IC performs frame change according to the frame change command VSYNC, and in order to increase the refresh rate of the display, one frame of the display screen is divided into a plurality of sub-frames for display.
Referring to the first row of fig. 9, a complete subframe includes P subframes, where P is an integer. Each sub-frame comprises m groups of display packets, where m is the number of rows of the display screen, i.e. a complete sub-frame comprises one display packet for all rows of the display screen. The display data of each line is divided into P groups, so that all the gray data of the display line is dispersed into all the sub-frames of the display frame, and the display unit in the application displays the display period of one display group. Taking the gray scale data of 13 bits as an example for explanation, assuming that the LED display screen includes 16 rows by 16 columns, and the gray scale data is divided into 32 display groups, 32 subframes are included in one complete display frame, and each subframe includes 16 display group data (one display group data in one row), that is, 16 display units are included in one subframe. Each group of display groups comprises 7-bit gray scale data, the gray scale data value of each group of display groups is 0-256, namely the PWM of the display group is 0-256, when the PWM =0, the gray scale data of the display group is 0, namely the time for the display unit to display the PWM is 0-256 display clock cycles, wherein the display clock cycles are the inherent clock of the system and are the unit duration of the PWM.
In a second aspect of this embodiment, another decoupling circuit is provided, which includes a pre-charge module and a constant current driving module, where an output terminal of the pre-charge module and an output terminal of the constant current driving module are connected together to serve as a channel output terminal. Unlike the foregoing embodiments, the present embodiment reduces one precharge state in both cases where PWM is greater than 0 and where PWM is equal to 0.
Referring to fig. 7, in a display unit, when PWM is greater than 0, the working states of the pre-charge module are pre-charge V1 and pre-charge off in sequence, the constant current driving module turns on the lamp beads based on PWM on the area corresponding to the pre-charge off, and at this time, the voltage at the output end of the channel is V3.
Referring to fig. 8, in one display unit, when PWM is equal to 0, the constant current driving module is turned off, and the output states of the precharge module are precharge V4, precharge V5, and precharge off in sequence.
A third aspect of the present embodiment provides a driver IC including the decoupling circuit of the foregoing embodiment, and the driver IC has a good decoupling effect.
The fourth aspect of the present embodiment provides a display device including a driver IC and a display panel, the driver IC and the display panel performing display, and the display panel including an LED display screen.
The foregoing is illustrative of the preferred embodiments of this application, and it is to be understood that this application is not limited to the forms disclosed herein, but is not intended to be exhaustive of other embodiments and that various other combinations, modifications, and environments may be used, and changes may be made within the scope of the inventive concept as described herein, by the above teachings or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the application, which is to be protected by the claims appended hereto.
Claims (10)
1. A decoupling circuit is characterized by comprising a pre-charge module and a constant current driving module, wherein the output end of the pre-charge module and the output end of the constant current driving module are connected together to serve as a channel output end;
in a display unit, when PWM is larger than 0, the working state of the pre-charging module is pre-charging V1, pre-charging closing and pre-charging V2 in sequence, the constant current driving module turns on a lamp bead in an area corresponding to the pre-charging closing based on PWM, and the voltage of the output end of a channel is V3 at the moment;
in one display unit, when the PWM is equal to 0, the constant current driving module is closed, and the output states of the pre-charging module are pre-charging V4, pre-charging V5 and pre-charging V6 in sequence;
wherein, (V1-V3) - (V4-V5) = K1, (V2-V3) - (V6-V5) = K2, and K1 and K2 are constants.
2. The decoupling circuit of claim 1, wherein the precharge off state lasts for a time equal to or greater than a display time of the PWM when the PWM is greater than 0.
3. The decoupling circuit of claim 1 wherein none of the pre-charges V1, V2, V4, V5, V6 are sufficient to light the lamp bead.
4. The decoupling circuit of claim 1 wherein V3< V5 in a common anode display screen and V3> V5 in a common cathode display screen.
5. The decoupling circuit of claim 1 wherein V3> V1, V3> V2, V5> V4 in a common cathode display screen;
in the common anode display screen, V3 is less than V1, V3 is less than V2, and V5 is less than V4.
6. The decoupling circuit of claim 1, wherein the precharge module includes an off state between V1 and V3, between V3 and V2, between V4 and V5, and between V5 and V6, the off state having a duration t, wherein t ≧ 0.
7. The decoupling circuit of claim 1 wherein said display cell is the smallest display grouping of gray scale data within a sub-frame.
8. A decoupling circuit is characterized by comprising a pre-charge module and a constant current driving module, wherein the output end of the pre-charge module and the output end of the constant current driving module are connected together to serve as a channel output end;
in a display unit, when PWM is larger than 0, the working state of the pre-charging module is pre-charging V1 and pre-charging off in sequence, the constant current driving module turns on a lamp bead in an area corresponding to the pre-charging off based on PWM, and the voltage of the output end of a channel is V3 at the moment;
in one display unit, when the PWM is equal to 0, the constant current driving module is closed, and the output states of the pre-charging module are pre-charging V4, pre-charging V5 and pre-charging closing in sequence;
wherein, (V1-V3) - (V4-V5) = K1, and K1 is a constant.
9. A driver IC comprising the decoupling circuit of any one of claims 1-8.
10. A display device comprising a driver IC and a display panel, the driver IC as claimed in claim 9, the display panel comprising an LED display screen.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211208890.6A CN115547244A (en) | 2022-09-30 | 2022-09-30 | Decoupling circuit, driving IC and display device |
| US18/457,083 US20240112624A1 (en) | 2022-09-30 | 2023-08-28 | Decoupling Circuit, Driving IC, and Display Device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202211208890.6A CN115547244A (en) | 2022-09-30 | 2022-09-30 | Decoupling circuit, driving IC and display device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115985235A (en) * | 2023-03-14 | 2023-04-18 | 合肥集创微电子科技有限公司 | LED driving circuit, driving method and display device |
| CN116403516A (en) * | 2023-06-05 | 2023-07-07 | 成都利普芯微电子有限公司 | Display driving method and display driving chip |
-
2022
- 2022-09-30 CN CN202211208890.6A patent/CN115547244A/en active Pending
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2023
- 2023-08-28 US US18/457,083 patent/US20240112624A1/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115985235A (en) * | 2023-03-14 | 2023-04-18 | 合肥集创微电子科技有限公司 | LED driving circuit, driving method and display device |
| CN116403516A (en) * | 2023-06-05 | 2023-07-07 | 成都利普芯微电子有限公司 | Display driving method and display driving chip |
| CN116403516B (en) * | 2023-06-05 | 2023-08-22 | 成都利普芯微电子有限公司 | Display driving method and display driving chip |
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| US20240112624A1 (en) | 2024-04-04 |
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